Core ControlDictionary doesn't recognize TextBlock

I am trying to automate capturing a System.Windows.Controls.TextBlock and get the text that is already existing there.
However it appears that the White library does not recognize this control and I get a NULL referenced exception.

It appears that the ControlDictionaryItem does not recognize the TextBlock control and which is why the problem occurs.
Has anyone tried to automate using the TextBlock control? If so can you suggest any workarounds / alternative to this problem?